Sept 9 - Abdominal, Back and Shoulder Region Flashcards
Name the two main groups of abdominal muscles
Anterior abdominal wall in front of the column (flexion).
Posterior abdominal wall behind the column (extension).
What is the importance of abdominal muscles?
They’re stabilizers that support the trunk and lower back
What function do the anterior abdominal muscles serve?
They serve a protective function
They cause movement of the trunk
They allow for changes in size of the cavity
Anterior abdominal muscles are innervated by:
intercostal nerves
Name the four anterior abdominal muscles
External abdominal oblique
Internal abdominal oblique
Transverse abdominal muscle (transversalis)
Rectus abdominus muscle
Describe the external abdominal oblique
It’s the outer most muscle on the anterior wall
It pushes pressure from the front inwards
Describe the internal abdominal oblique
It runs perpendicular to the external to the external oblique
It’s deep to external oblique
It functions with the external oblique to power “same side rotation”
Describe the transverse abdominal muscle
It connects the ribcage and pelvic bone
It forms a front platform
It flattens the lordotic curve of the spine
It stabilizes the anterior abdominal wall
Describe the rectus abdominus muscle
Most superficial pair of muscles run up either side of the mid-line of the abdomen
Identified by their bulging segments created by connective tissue divisions called Tendinous
Divides muscle into 4 sections (8-pack)
Name the three posterior abdominal wall muscles
Erector spinae
Iliacus muscle
Psoas major muscle
Describe the erector spinae group
Large column of muscle on either side of the vertebral column
Important for extension of the spine, but it also works against gravity to control trunk flexion (bending over)
It is often described as a single muscle, but it comprised of three muscles
Name the three muscles comprising the erector spinae group
Iliocostalis
Longissimus
Spinalis
Describe the quadratus lumborum
It powers lateral flexion of the lumbar spine
Stabilizes the twelfth rib against the action of the diaphragm during inspiration
What is the iliopsoas?
The term that refers to the psoas major and the iliacus. It was given because they share a common tendon.
Desribe the iliopsoas
The psoas major and iliacus muscles are deep to the abdominal contents adjacent to the vertebral column and within the pelvic cavity. Together they power hip flexion and are innervated by the femoral nerve. They also stabilize the back (important for climbing stairs)
What is the rule of 3, regarding the shoulder girdle
It is comprised of 3 bones, 3 joints and 3 ligaments.
What is the role of the shoulder girlde
It represents the only attachment of the appendicular skeleton (arm) to the axial skeleton (trunk)
Name the three bones of the shoulder girlde
Clavicle (aka the collar bone)
Scapula (aka the shoulder blade)
Humerus (aka the arm)
Describe the clavicle
Superficial, “S” shaped bone that acts like a strut (keeps shoulders back and arms at side). Medial third is convex, lateral third is concave (anteriorly).
It defines the broadness of shoulders.
Functions: force absorption, dissipation of force & rotation of the scapula in abduction
Describe the scapula
Spade-like, broad based bone. It’s thin, flat, triangular with 3 borders
There is NO attachment to chest wall
It’s held against the ribs by muscles
Name the three borders that comprise the scapula
The medial border runs along the vertebral column
The lateral border
The superior border
What is the acromiom process?
It’s the most lateral section of the scapula
It’s the part that’s in direct contact with the clavicle - forms a joint called the AC joint